Listen-before-talk failure reporting for sidelink channels

ABSTRACT

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may detect, while transmitting data using at least one first bandwidth on at least one sidelink channel to at least one other UE, one or more failures of a listen-before-talk (LBT) procedure within an amount of time. The UE may transmit, to at least one of a base station or the at least one other UE, a report indicating the one or more failures. Numerous other aspects are described.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wirelesscommunication and to techniques and apparatuses for listen-before-talkfailure reporting for sidelink channels.

BACKGROUND

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources (e.g., bandwidth,transmit power, or the like). Examples of such multiple-accesstechnologies include code division multiple access (CDMA) systems, timedivision multiple access (TDMA) systems, frequency-division multipleaccess (FDMA) systems, orthogonal frequency-division multiple access(OFDMA) systems, single-carrier frequency-division multiple access(SC-FDMA) systems, time division synchronous code division multipleaccess (TD-SCDMA) systems, and Long Term Evolution (LTE).LTE/LTE-Advanced is a set of enhancements to the Universal MobileTelecommunications System (UMTS) mobile standard promulgated by theThird Generation Partnership Project (3GPP).

A wireless network may include a number of base stations (BSs) that cansupport communication for a number of user equipment (UEs). A userequipment (UE) may communicate with a base station (BS) via the downlinkand uplink. The downlink (or forward link) refers to the communicationlink from the BS to the UE, and the uplink (or reverse link) refers tothe communication link from the UE to the BS. As will be described inmore detail herein, a BS may be referred to as a Node B, a gNB, anaccess point (AP), a radio head, a transmit receive point (TRP), a NewRadio (NR) BS, a 5G Node B, or the like.

The above multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent user equipment to communicate on a municipal, national,regional, and even global level. NR, which may also be referred to as5G, is a set of enhancements to the LTE mobile standard promulgated bythe 3GPP. NR is designed to better support mobile broadband Internetaccess by improving spectral efficiency, lowering costs, improvingservices, making use of new spectrum, and better integrating with otheropen standards using orthogonal frequency division multiplexing (OFDM)with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL), using CP-OFDMand/or SC-FDM (e.g., also known as discrete Fourier transform spreadOFDM (DFT-s-OFDM)) on the uplink (UL), as well as supportingbeamforming, multiple-input multiple-output (MIMO) antenna technology,and carrier aggregation. As the demand for mobile broadband accesscontinues to increase, further improvements in LTE, NR, and other radioaccess technologies remain useful.

SUMMARY

In some aspects, a user equipment (UE) for wireless communicationincludes a memory and one or more processors operatively coupled to thememory, the memory and the one or more processors configured to detect,while transmitting data using at least one first bandwidth on at leastone sidelink channel to at least one other UE, one or more failures of alisten-before-talk (LBT) procedure within an amount of time; andtransmit, to at least one of a base station or the at least one otherUE, a report indicating the one or more failures.

In some aspects, a base station for wireless communication includes amemory and one or more processors operatively coupled to the memory, thememory and the one or more processors configured to receive, from a UE,a report indicating one or more failures of an LBT procedure associatedwith at least one first bandwidth on at least one sidelink channel; andtransmit, to the UE, an indication of at least one second bandwidth touse on the at least one sidelink channel.

In some aspects, a method of wireless communication performed by a UEincludes detecting, while transmitting data using at least one firstbandwidth on at least one sidelink channel to at least one other UE, oneor more failures of an LBT procedure within an amount of time; andtransmitting, to at least one of a base station or the at least oneother UE, a report indicating the one or more failures.

In some aspects, a method of wireless communication performed by a basestation includes receiving, from a UE, a report indicating one or morefailures of an LBT procedure associated with at least one firstbandwidth on at least one sidelink channel; and transmitting, to the UE,an indication of at least one second bandwidth to use on the at leastone sidelink channel.

In some aspects, a non-transitory computer-readable medium storing a setof instructions for wireless communication includes one or moreinstructions that, when executed by one or more processors of a UE,cause the UE to detect, while transmitting data using at least one firstbandwidth on at least one sidelink channel to at least one other UE, oneor more failures of an LBT procedure within an amount of time; andtransmit, to at least one of a base station or the at least one otherUE, a report indicating the one or more failures.

In some aspects, a non-transitory computer-readable medium storing a setof instructions for wireless communication includes one or moreinstructions that, when executed by one or more processors of a basestation, cause the base station to receive, from a UE, a reportindicating one or more failures of an LBT procedure associated with atleast one first bandwidth on at least one sidelink channel; andtransmit, to the UE, an indication of at least one second bandwidth touse on the at least one sidelink channel.

In some aspects, an apparatus for wireless communication includes meansfor detecting, while transmitting data using at least one firstbandwidth on at least one sidelink channel to at least one other UE, oneor more failures of an LBT procedure within an amount of time; and meansfor transmitting, to at least one of a base station or the at least oneother UE, a report indicating the one or more failures.

In some aspects, an apparatus for wireless communication includes meansfor receiving, from a UE, a report indicating one or more failures of anLBT procedure associated with at least one first bandwidth on at leastone sidelink channel; and means for transmitting, to the UE, anindication of at least one second bandwidth to use on the at least onesidelink channel.

Aspects generally include a method, apparatus, system, computer programproduct, non-transitory computer-readable medium, user equipment, basestation, wireless communication device, and/or processing system assubstantially described herein with reference to and as illustrated bythe drawings and specification.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purposesof illustration and description, and not as a definition of the limitsof the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the above-recited features of the present disclosure can beunderstood in detail, a more particular description, briefly summarizedabove, may be had by reference to aspects, some of which are illustratedin the appended drawings. It is to be noted, however, that the appendeddrawings illustrate only certain typical aspects of this disclosure andare therefore not to be considered limiting of its scope, for thedescription may admit to other equally effective aspects. The samereference numbers in different drawings may identify the same or similarelements.

FIG. 1 is a diagram illustrating an example of a wireless network, inaccordance with various aspects of the present disclosure.

FIG. 2 is a diagram illustrating an example of a base station incommunication with a UE in a wireless network, in accordance withvarious aspects of the present disclosure.

FIG. 3 is a diagram illustrating an example of sidelink communications,in accordance with various aspects of the present disclosure.

FIG. 4 is a diagram illustrating an example of sidelink communicationsand access link communications, in accordance with various aspects ofthe present disclosure.

FIG. 5 is a diagram illustrating an example associated withlisten-before-talk (LBT) failure reporting for sidelink channels, inaccordance with various aspects of the present disclosure.

FIGS. 6-7 are diagrams illustrating example processes associated withLBT failure reporting for sidelink channels, in accordance with variousaspects of the present disclosure.

FIGS. 8-9 are block diagrams of example apparatuses for wirelesscommunication, in accordance with various aspects of the presentdisclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafterwith reference to the accompanying drawings. This disclosure may,however, be embodied in many different forms and should not be construedas limited to any specific structure or function presented throughoutthis disclosure. Rather, these aspects are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope of the disclosure to those skilled in the art. Based on theteachings herein, one skilled in the art should appreciate that thescope of the disclosure is intended to cover any aspect of thedisclosure disclosed herein, whether implemented independently of orcombined with any other aspect of the disclosure. For example, anapparatus may be implemented or a method may be practiced using anynumber of the aspects set forth herein. In addition, the scope of thedisclosure is intended to cover such an apparatus or method which ispracticed using other structure, functionality, or structure andfunctionality in addition to or other than the various aspects of thedisclosure set forth herein. It should be understood that any aspect ofthe disclosure disclosed herein may be embodied by one or more elementsof a claim.

Several aspects of telecommunication systems will now be presented withreference to various apparatuses and techniques. These apparatuses andtechniques will be described in the following detailed description andillustrated in the accompanying drawings by various blocks, modules,components, circuits, steps, processes, algorithms, or the like(collectively referred to as “elements”). These elements may beimplemented using hardware, software, or combinations thereof. Whethersuch elements are implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem.

It should be noted that while aspects may be described herein usingterminology commonly associated with a 5G or NR radio access technology(RAT), aspects of the present disclosure can be applied to other RATs,such as a 3G RAT, a 4G RAT, and/or a RAT subsequent to 5G (e.g., 6G).

FIG. 1 is a diagram illustrating an example of a wireless network 100,in accordance with various aspects of the present disclosure. Thewireless network 100 may be or may include elements of a 5G (NR) networkand/or an LTE network, among other examples. The wireless network 100may include a number of base stations 110 (shown as BS 110 a, BS 110 b,BS 110 c, and BS 110 d) and other network entities. A base station (BS)is an entity that communicates with user equipment (UEs) and may also bereferred to as an NR BS, a Node B, a gNB, a 5G node B (NB), an accesspoint, a transmit receive point (TRP), or the like. Each BS may providecommunication coverage for a particular geographic area. In 3GPP, theterm “cell” can refer to a coverage area of a BS and/or a BS subsystemserving this coverage area, depending on the context in which the termis used.

ABS may provide communication coverage for a macro cell, a pico cell, afemto cell, and/or another type of cell. A macro cell may cover arelatively large geographic area (e.g., several kilometers in radius)and may allow unrestricted access by UEs with service subscription. Apico cell may cover a relatively small geographic area and may allowunrestricted access by UEs with service subscription. A femto cell maycover a relatively small geographic area (e.g., a home) and may allowrestricted access by UEs having association with the femto cell (e.g.,UEs in a closed subscriber group (CSG)). A BS for a macro cell may bereferred to as a macro BS. A BS for a pico cell may be referred to as apico BS. A BS for a femto cell may be referred to as a femto BS or ahome BS. In the example shown in FIG. 1 , a BS 110 a may be a macro BSfor a macro cell 102 a, a BS 110 b may be a pico BS for a pico cell 102b, and a BS 110 c may be a femto BS for a femto cell 102 c. ABS maysupport one or multiple (e.g., three) cells. The terms “eNB”, “basestation”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” maybe used interchangeably herein.

In some aspects, a cell may not necessarily be stationary, and thegeographic area of the cell may move according to the location of amobile BS. In some aspects, the BSs may be interconnected to one anotherand/or to one or more other BSs or network nodes (not shown) in thewireless network 100 through various types of backhaul interfaces, suchas a direct physical connection or a virtual network, using any suitabletransport network.

Wireless network 100 may also include relay stations. A relay station isan entity that can receive a transmission of data from an upstreamstation (e.g., a BS or a UE) and send a transmission of the data to adownstream station (e.g., a UE or a BS). A relay station may also be aUE that can relay transmissions for other UEs. In the example shown inFIG. 1 , a relay BS 110 d may communicate with macro BS 110 a and a UE120 d in order to facilitate communication between BS 110 a and UE 120d. A relay BS may also be referred to as a relay station, a relay basestation, a relay, or the like.

Wireless network 100 may be a heterogeneous network that includes BSs ofdifferent types, such as macro BSs, pico BSs, femto BSs, relay BSs, orthe like. These different types of BSs may have different transmit powerlevels, different coverage areas, and different impacts on interferencein wireless network 100. For example, macro BSs may have a high transmitpower level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relayBSs may have lower transmit power levels (e.g., 0.1 to 2 watts).

A network controller 130 may couple to a set of BSs and may providecoordination and control for these BSs. Network controller 130 maycommunicate with the BSs via a backhaul. The BSs may also communicatewith one another, directly or indirectly, via a wireless or wirelinebackhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wirelessnetwork 100, and each UE may be stationary or mobile. A UE may also bereferred to as an access terminal, a terminal, a mobile station, asubscriber unit, a station, or the like. A UE may be a cellular phone(e.g., a smart phone), a personal digital assistant (PDA), a wirelessmodem, a wireless communication device, a handheld device, a laptopcomputer, a cordless phone, a wireless local loop (WLL) station, atablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook,a medical device or equipment, biometric sensors/devices, wearabledevices (smart watches, smart clothing, smart glasses, smart wristbands, smart jewelry (e.g., smart ring, smart bracelet)), anentertainment device (e.g., a music or video device, or a satelliteradio), a vehicular component or sensor, smart meters/sensors,industrial manufacturing equipment, a global positioning system device,or any other suitable device that is configured to communicate via awireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolvedor enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEsinclude, for example, robots, drones, remote devices, sensors, meters,monitors, and/or location tags, that may communicate with a basestation, another device (e.g., remote device), or some other entity. Awireless node may provide, for example, connectivity for or to a network(e.g., a wide area network such as Internet or a cellular network) via awired or wireless communication link. Some UEs may be consideredInternet-of-Things (IoT) devices, and/or may be implemented as NB-IoT(narrowband internet of things) devices. Some UEs may be considered aCustomer Premises Equipment (CPE). UE 120 may be included inside ahousing that houses components of UE 120, such as processor componentsand/or memory components. In some aspects, the processor components andthe memory components may be coupled together. For example, theprocessor components (e.g., one or more processors) and the memorycomponents (e.g., a memory) may be operatively coupled, communicativelycoupled, electronically coupled, and/or electrically coupled.

In general, any number of wireless networks may be deployed in a givengeographic area. Each wireless network may support a particular RAT andmay operate on one or more frequencies. A RAT may also be referred to asa radio technology, an air interface, or the like. A frequency may alsobe referred to as a carrier, a frequency channel, or the like. Eachfrequency may support a single RAT in a given geographic area in orderto avoid interference between wireless networks of different RATs. Insome cases, NR or 5G RAT networks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120 a and UE 120e) may communicate directly using one or more sidelink channels (e.g.,without using a base station 110 as an intermediary to communicate withone another). For example, the UEs 120 may communicate usingpeer-to-peer (P2P) communications, device-to-device (D2D)communications, a vehicle-to-everything (V2X) protocol (e.g., which mayinclude a vehicle-to-vehicle (V2V) protocol or avehicle-to-infrastructure (V2I) protocol), and/or a mesh network. Inthis case, the UE 120 may perform scheduling operations, resourceselection operations, and/or other operations described elsewhere hereinas being performed by the base station 110.

Devices of wireless network 100 may communicate using theelectromagnetic spectrum, which may be subdivided based on frequency orwavelength into various classes, bands, channels, or the like. Forexample, devices of wireless network 100 may communicate using anoperating band having a first frequency range (FR1), which may span from410 MHz to 7.125 GHz, and/or may communicate using an operating bandhaving a second frequency range (FR2), which may span from 24.25 GHz to52.6 GHz. The frequencies between FR1 and FR2 are sometimes referred toas mid-band frequencies. Although a portion of FR1 is greater than 6GHz, FR1 is often referred to as a “sub-6 GHz” band. Similarly, FR2 isoften referred to as a “millimeter wave” band despite being differentfrom the extremely high frequency (EHF) band (30 GHz-300 GHz) which isidentified by the International Telecommunications Union (ITU) as a“millimeter wave” band. Thus, unless specifically stated otherwise, itshould be understood that the term “sub-6 GHz” or the like, if usedherein, may broadly represent frequencies less than 6 GHz, frequencieswithin FR1, and/or mid-band frequencies (e.g., greater than 7.125 GHz).Similarly, unless specifically stated otherwise, it should be understoodthat the term “millimeter wave” or the like, if used herein, may broadlyrepresent frequencies within the EHF band, frequencies within FR2,and/or mid-band frequencies (e.g., less than 24.25 GHz). It iscontemplated that the frequencies included in FR1 and FR2 may bemodified, and techniques described herein are applicable to thosemodified frequency ranges.

As indicated above, FIG. 1 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 1 .

FIG. 2 is a diagram illustrating an example 200 of a base station 110 incommunication with a UE 120 in a wireless network 100, in accordancewith various aspects of the present disclosure. Base station 110 may beequipped with T antennas 234 a through 234 t, and UE 120 may be equippedwith R antennas 252 a through 252 r, where in general T≥1 and R≥1.

At base station 110, a transmit processor 220 may receive data from adata source 212 for one or more UEs, select one or more modulation andcoding schemes (MCS) for each UE based at least in part on channelquality indicators (CQIs) received from the UE, process (e.g., encodeand modulate) the data for each UE based at least in part on the MCS(s)selected for the UE, and provide data symbols for all UEs. Transmitprocessor 220 may also process system information (e.g., for semi-staticresource partitioning information (SRPI)) and control information (e.g.,CQI requests, grants, and/or upper layer signaling) and provide overheadsymbols and control symbols. Transmit processor 220 may also generatereference symbols for reference signals (e.g., a cell-specific referencesignal (CRS) or a demodulation reference signal (DMRS)) andsynchronization signals (e.g., a primary synchronization signal (PSS) ora secondary synchronization signal (SSS)). A transmit (TX)multiple-input multiple-output (MIMO) processor 230 may perform spatialprocessing (e.g., precoding) on the data symbols, the control symbols,the overhead symbols, and/or the reference symbols, if applicable, andmay provide T output symbol streams to T modulators (MODs) 232 a through232 t. Each modulator 232 may process a respective output symbol stream(e.g., for OFDM) to obtain an output sample stream. Each modulator 232may further process (e.g., convert to analog, amplify, filter, andupconvert) the output sample stream to obtain a downlink signal. Tdownlink signals from modulators 232 a through 232 t may be transmittedvia T antennas 234 a through 234 t, respectively.

At UE 120, antennas 252 a through 252 r may receive the downlink signalsfrom base station 110 and/or other base stations and may providereceived signals to demodulators (DEMODs) 254 a through 254 r,respectively. Each demodulator 254 may condition (e.g., filter, amplify,downconvert, and digitize) a received signal to obtain input samples.Each demodulator 254 may further process the input samples (e.g., forOFDM) to obtain received symbols. A MIMO detector 256 may obtainreceived symbols from all R demodulators 254 a through 254 r, performMIMO detection on the received symbols if applicable, and providedetected symbols. A receive processor 258 may process (e.g., demodulateand decode) the detected symbols, provide decoded data for UE 120 to adata sink 260, and provide decoded control information and systeminformation to a controller/processor 280. The term“controller/processor” may refer to one or more controllers, one or moreprocessors, or a combination thereof. A channel processor may determinea reference signal received power (RSRP) parameter, a received signalstrength indicator (RSSI) parameter, a reference signal received quality(RSRQ) parameter, and/or a channel quality indicator (CQI) parameter,among other examples. In some aspects, one or more components of UE 120may be included in a housing 284.

Network controller 130 may include communication unit 294,controller/processor 290, and memory 292. Network controller 130 mayinclude, for example, one or more devices in a core network. Networkcontroller 130 may communicate with base station 110 via communicationunit 294.

Antennas (e.g., antennas 234 a through 234 t and/or antennas 252 athrough 252 r) may include, or may be included within, one or moreantenna panels, antenna groups, sets of antenna elements, and/or antennaarrays, among other examples. An antenna panel, an antenna group, a setof antenna elements, and/or an antenna array may include one or moreantenna elements. An antenna panel, an antenna group, a set of antennaelements, and/or an antenna array may include a set of coplanar antennaelements and/or a set of non-coplanar antenna elements. An antennapanel, an antenna group, a set of antenna elements, and/or an antennaarray may include antenna elements within a single housing and/orantenna elements within multiple housings. An antenna panel, an antennagroup, a set of antenna elements, and/or an antenna array may includeone or more antenna elements coupled to one or more transmission and/orreception components, such as one or more components of FIG. 2 .

On the uplink, at UE 120, a transmit processor 264 may receive andprocess data from a data source 262 and control information (e.g., forreports that include RSRP, RSSI, RSRQ, and/or CQI) fromcontroller/processor 280. Transmit processor 264 may also generatereference symbols for one or more reference signals. The symbols fromtransmit processor 264 may be precoded by a TX MIMO processor 266 ifapplicable, further processed by modulators 254 a through 254 r (e.g.,for DFT-s-OFDM or CP-OFDM), and transmitted to base station 110. In someaspects, a modulator and a demodulator (e.g., MOD/DEMOD 254) of the UE120 may be included in a modem of the UE 120. In some aspects, the UE120 includes a transceiver. The transceiver may include any combinationof antenna(s) 252, modulators and/or demodulators 254, MIMO detector256, receive processor 258, transmit processor 264, and/or TX MIMOprocessor 266. The transceiver may be used by a processor (e.g.,controller/processor 280) and memory 282 to perform aspects of any ofthe methods described herein, for example, as described with referenceto FIGS. 5-7 .

At base station 110, the uplink signals from UE 120 and other UEs may bereceived by antennas 234, processed by demodulators 232, detected by aMIMO detector 236 if applicable, and further processed by a receiveprocessor 238 to obtain decoded data and control information sent by UE120. Receive processor 238 may provide the decoded data to a data sink239 and the decoded control information to controller/processor 240.Base station 110 may include communication unit 244 and communicate tonetwork controller 130 via communication unit 244. Base station 110 mayinclude a scheduler 246 to schedule UEs 120 for downlink and/or uplinkcommunications. In some aspects, a modulator and a demodulator (e.g.,MOD/DEMOD 232) of the base station 110 may be included in a modem of thebase station 110. In some aspects, the base station 110 includes atransceiver. The transceiver may include any combination of antenna(s)234, modulators and/or demodulators 232, MIMO detector 236, receiveprocessor 238, transmit processor 220, and/or TX MIMO processor 230. Thetransceiver may be used by a processor (e.g., controller/processor 240)and memory 242 to perform aspects of any of the methods describedherein, for example, as described with reference to FIGS. 5-7 .

Controller/processor 240 of base station 110, controller/processor 280of UE 120, and/or any other component(s) of FIG. 2 may perform one ormore techniques associated with LBT failure reporting for sidelinkchannels, as described in more detail elsewhere herein. For example,controller/processor 240 of base station 110, controller/processor 280of UE 120, and/or any other component(s) of FIG. 2 may perform or directoperations of, for example, process 600 of FIG. 6 , process 700 of FIG.7 , and/or other processes as described herein. Memories 242 and 282 maystore data and program codes for base station 110 and UE 120,respectively. In some aspects, memory 242 and/or memory 282 may includea non-transitory computer-readable medium storing one or moreinstructions (e.g., code and/or program code) for wirelesscommunication. For example, the one or more instructions, when executed(e.g., directly, or after compiling, converting, and/or interpreting) byone or more processors of the base station 110 and/or the UE 120, maycause the one or more processors, the UE 120, and/or the base station110 to perform or direct operations of, for example, process 600 of FIG.6 , process 700 of FIG. 7 , and/or other processes as described herein.In some aspects, executing instructions may include running theinstructions, converting the instructions, compiling the instructions,and/or interpreting the instructions, among other examples.

In some aspects, a UE (e.g., apparatus 800 of FIG. 8 , Tx UE 305-1 ofFIG. 5 , and/or UE 120) may include means for detecting, whiletransmitting data using at least one first bandwidth on at least onesidelink channel to at least one other UE, one or more failures of anLBT procedure within an amount of time; and/or means for transmitting,to at least one of a base station or the at least one other UE, a reportindicating the one or more failures. The means for the UE to performoperations described herein may include, for example, one or more ofantenna 252, demodulator 254, MIMO detector 256, receive processor 258,transmit processor 264, TX MIMO processor 266, modulator 254,controller/processor 280, or memory 282.

In some aspects, the UE may further include means for receiving at leastone configuration message from the base station, wherein the amount oftime is based at least in part on the at least one configurationmessage. In some aspects, the UE may further include means forretransmitting the data, to the at least one other UE, using at leastone second bandwidth on the at least one sidelink channel. Additionally,or alternatively, the UE may further include means for canceling pendingtransmissions based at least in part on detecting the one or morefailures; and/or means for ceasing transmitting one or more broadcastsignals based at least in part on detecting the one or more failures.

In some aspects, a base station (e.g., apparatus 900 of FIG. 9 and/orbase station 110) may include means for receiving, from a UE (e.g.,apparatus 800 of FIG. 8 , Tx UE 305-1 of FIG. 5 , and/or UE 120), areport indicating one or more failures of an LBT procedure associatedwith at least one first bandwidth on at least one sidelink channel;and/or means for transmitting, to the UE, an indication of at least onesecond bandwidth to use on the at least one sidelink channel. The meansfor the base station to perform operations described herein may include,for example, one or more of transmit processor 220, TX MIMO processor230, modulator 232, antenna 234, demodulator 232, MIMO detector 236,receive processor 238, controller/processor 240, memory 242, orscheduler 246.

In some aspects, the base station may further include means fortransmitting at least one configuration message to the UE, wherein theone or more failures are associated with an amount of time that is basedat least in part on the at least one configuration message.

While blocks in FIG. 2 are illustrated as distinct components, thefunctions described above with respect to the blocks may be implementedin a single hardware, software, or combination component or in variouscombinations of components. For example, the functions described withrespect to the transmit processor 264, the receive processor 258, and/orthe TX MIMO processor 266 may be performed by or under the control ofcontroller/processor 280.

As indicated above, FIG. 2 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 2 .

FIG. 3 is a diagram illustrating an example 300 of sidelinkcommunications, in accordance with various aspects of the presentdisclosure. As shown in FIG. 3 , a first UE 305-1 may communicate with asecond UE 305-2 (and one or more other UEs 305) via one or more sidelinkchannels 310. The UEs 305-1 and 305-2 may communicate using the one ormore sidelink channels 310 for P2P communications, D2D communications,V2X communications (e.g., which may include V2V communications, V2Icommunications, V2P communications, and/or the like), mesh networking,and/or the like. In some aspects, the UEs 305 (e.g., UE 305-1 and/or UE305-2) may correspond to one or more other UEs described elsewhereherein, such as UE 120. In some aspects, the one or more sidelinkchannels 310 may use a PC5 interface and/or may operate in a highfrequency band (e.g., the 5.9 GHz band). Additionally, or alternatively,the UEs 305 may synchronize timing of transmission time intervals (TTIs)(e.g., frames, subframes, slots, symbols, and/or the like) using globalnavigation satellite system (GNSS) timing.

As further shown in FIG. 3 , the one or more sidelink channels 310 mayinclude a physical sidelink control channel (PSCCH) 315, a physicalsidelink shared channel (PSSCH) 320, and/or a physical sidelink feedbackchannel (PSFCH) 325. The PSCCH 315 may be used to communicate controlinformation, similar to a physical downlink control channel (PDCCH)and/or a physical uplink control channel (PUCCH) used for cellularcommunications with a base station 110 via an access link or an accesschannel. The PSSCH 320 may be used to communicate data, similar to aphysical downlink shared channel (PDSCH) and/or a physical uplink sharedchannel (PUSCH) used for cellular communications with a base station 110via an access link or an access channel. For example, the PSCCH 315 maycarry sidelink control information (SCI) 330, which may indicate variouscontrol information used for sidelink communications, such as one ormore resources (e.g., time resources, frequency resources, spatialresources, and/or the like) where a transport block (TB) 335 may becarried on the PSSCH 320. The TB 335 may include data. The PSFCH 325 maybe used to communicate sidelink feedback 340, such as hybrid automaticrepeat request (HARQ) feedback (e.g., acknowledgement or negativeacknowledgement (ACK/NACK) information), transmit power control (TPC), ascheduling request (SR), and/or the like.

In some aspects, the one or more sidelink channels 310 may use resourcepools. For example, a scheduling assignment (e.g., included in SCI 330)may be transmitted in sub-channels using specific resource blocks (RBs)across time. In some aspects, data transmissions (e.g., on the PSSCH320) associated with a scheduling assignment may occupy adjacent RBs inthe same subframe as the scheduling assignment (e.g., using frequencydivision multiplexing). In some aspects, a scheduling assignment andassociated data transmissions are not transmitted on adjacent RBs.

In some aspects, a UE 305 may operate using a transmission mode whereresource selection and/or scheduling is performed by the UE 305 (e.g.,rather than a base station 110). In some aspects, the UE 305 may performresource selection and/or scheduling by sensing channel availability fortransmissions. For example, the UE 305 may measure a received signalstrength indicator (RSSI) parameter (e.g., a sidelink-RSSI (S-RSSI)parameter) associated with various sidelink channels, may measure areference signal received power (RSRP) parameter (e.g., a PSSCH-RSRPparameter) associated with various sidelink channels, may measure areference signal received quality (RSRQ) parameter (e.g., a PSSCH-RSRQparameter) associated with various sidelink channels, and/or the like,and may select a channel for transmission of a sidelink communicationbased at least in part on the measurement(s).

Additionally, or alternatively, the UE 305 may perform resourceselection and/or scheduling using SCI 330 received in the PSCCH 315,which may indicate occupied resources, channel parameters, and/or thelike. Additionally, or alternatively, the UE 305 may perform resourceselection and/or scheduling by determining a channel busy rate (CBR)associated with various sidelink channels, which may be used for ratecontrol (e.g., by indicating a maximum number of resource blocks thatthe UE 305 can use for a particular set of subframes).

In the transmission mode where resource selection and/or scheduling isperformed by a UE 305, the UE 305 may generate sidelink grants, and maytransmit the grants in SCI 330. A sidelink grant may indicate, forexample, one or more parameters (e.g., transmission parameters) to beused for an upcoming sidelink transmission, such as one or more resourceblocks to be used for the upcoming sidelink transmission on the PSSCH320 (e.g., for TBs 335), one or more subframes to be used for theupcoming sidelink transmission, a modulation and coding scheme (MCS) tobe used for the upcoming sidelink transmission, and/or the like. In someaspects, a UE 305 may generate a sidelink grant that indicates one ormore parameters for semi-persistent scheduling (SPS), such as aperiodicity of a sidelink transmission. Additionally, or alternatively,the UE 305 may generate a sidelink grant for event-driven scheduling,such as for an on-demand sidelink message.

As indicated above, FIG. 3 is provided as an example. Other examples maydiffer from what is described with respect to FIG. 3 .

FIG. 4 is a diagram illustrating an example 400 of sidelinkcommunications and access link communications, in accordance withvarious aspects of the present disclosure. As shown in FIG. 4 , atransmitter (Tx)/receiver (Rx) UE 405 and an Rx/Tx UE 410 maycommunicate with one another via a sidelink, as described above inconnection with FIG. 3 . As further shown, in some sidelink modes, abase station 110 may communicate with the Tx/Rx UE 405 via a firstaccess link. Additionally, or alternatively, in some sidelink modes, thebase station 110 may communicate with the Rx/Tx UE 410 via a secondaccess link. The Tx/Rx UE 405 and/or the Rx/Tx UE 410 may correspond toone or more UEs described elsewhere herein, such as the UE 120 of FIG. 1. Thus, a direct link between UEs 120 (e.g., via a PC5 interface) may bereferred to as a sidelink, and a direct link between a base station 110and a UE 120 (e.g., via a Uu interface) may be referred to as an accesslink. Sidelink communications may be transmitted via the sidelink, andaccess link communications may be transmitted via the access link. Anaccess link communication may be either a downlink communication (from abase station 110 to a UE 120) or an uplink communication (from a UE 120to a base station 110).

As indicated above, FIG. 4 is provided as an example. Other examples maydiffer from what is described with respect to FIG. 4 .

Sidelink channels may be scheduled by a base station (e.g., according tomode 1 PC5 as defined in 3GPP specifications and/or another standard).Accordingly, a base station may transmit one or more configurationmessages to a transmitting (Tx) UE that indicate one or more resources(e.g., bandwidths, frequencies, slots or other time periods, and/orspatial filters such as beams) to use when the Tx UE transmits to areceiving (Rx) UE on a sidelink channel. As an alternative, sidelinkchannels may be scheduled by the Tx UE without base station involvement(e.g., according to mode 2 PC5 as defined in 3GPP specifications and/oranother standard). Accordingly, the Tx UE may transmit first SCI (SCI1)to reserve one or more resources for the sidelink channel and thentransmit second SCI (SCI2) to schedule transmissions to the Rx UE onthat sidelink channel. The Tx UE may transmit to a single Rx UE (e.g.,using a unicast link on the sidelink channel), to a plurality of Rx UEs(e.g., using a groupcast link, also referred to as a multicast link, onthe sidelink channel), and/or to any Rx UEs within a geographic area(e.g., by broadcasting on the sidelink channel).

In both mode 1 and mode 2, a Tx UE may use an LBT procedure on at leastone sidelink channel. For example, the Tx UE may wait for one or moresymbols of a slot (e.g., a portion of a radio frame), and transmit(e.g., to an Rx UE) within that slot only when the Tx UE does not decodea transmission in those one or more symbols. The Tx UE may wait for apreconfigured amount of time or for a dynamic amount of time (e.g.,determined based on a minimum amount of time, a maximum amount of time,an energy level associated with the transmission, a power class of theTx UE, an antenna gain associated with the Rx UE, and/or anothervariable). Accordingly, the LBT procedure may include a carrier sensingmultiple access (CSMA) procedure, a clear channel assessment (CCA)procedure, a carrier sensing adaptive transmission (CSAT) procedure,and/or another similar procedure. For example, the Tx UE may use an LBTprocedure as set forth in the Institute of Electrical and ElectronicsEngineers (IEEE) LAN/MAN Standards Committee 802.11 standards, the IEEEWireless Coexistence Technical Advisory Group (TAG) 802.19 standards,the European Telecommunications Standards Institute (ETSI) HarmonisedEuropean Standard (EN) 300 328, and/or another standard. The Tx UE mayuse the LBT procedure at least in part because the at least one sidelinkchannel is over an unlicensed band channel. For example, the at leastone sidelink channel may use NR unlicensed (NR-U) spectrum.

The Tx UE may detect one or more LBT failures on a sidelink channel. Forexample, the Tx UE may detect failure of a CSMA procedure, a CCAprocedure, a CSAT procedure, and/or another LBT procedure. However, theTx UE generally continues to attempt (using an LBT procedure) totransmit on the sidelink channel. Accordingly, continued LBT procedurefailures may result in reduced quality and/or reliability of sidelinkcommunications as well as increased latency and wasted processingresources.

Some techniques and apparatuses described herein enable a Tx UE (e.g.,UE 305-1 and/or UE 120) to report one or more LBT failures on a sidelinkchannel to a base station (e.g., base station 110) and/or at least oneRx UE (e.g., UE 305-2 and/or UE 120). As a result, in mode 1, the Tx UE305-1 may obtain one or more new resources from the base station 110 touse on the sidelink channel in order to increase quality and/orreliability of sidelink communications as well as conserve processingresources. In mode 2, the Tx UE 305-1 may report the one or more LBTfailures to the Rx UE 305-2 such that the Rx UE 305-2 may conserveprocessing resources. Additionally, in some aspects, the Tx UE 305-1 mayconfigure a new sidelink channel with the Rx UE 305-2, based at least inpart on the one or more LBT failures, in order to increase qualityand/or reliability of sidelink communications.

FIG. 5 is a diagram illustrating an example 500 associated with LBTfailure reporting for sidelink channels, in accordance with variousaspects of the present disclosure. As shown in FIG. 5 , example 500includes communication between a Tx UE 305-1 and an Rx UE 305-2. In someaspects, the Tx UE 305-1 and the Rx UE 305-2 may communicate on at leastone sidelink channel (e.g., as described above in connection with FIGS.3 and 4 ). In some aspects, the at least one sidelink channel mayinclude a physical sidelink broadcast channel (PSBCH), a PSCCH, a PSSCH,a PSFCH, and/or another sidelink channel. In some aspects, the Tx UE305-1 may schedule sidelink communications to the Rx UE 305-2 withoutbase station involvement (e.g., according to mode 2 PC5 as defined in3GPP specifications and/or another standard). As an alternative, example500 may further include communications between a base station 110 andthe Tx UE 305-1. For example, the base station 110 may transmit one ormore configuration messages to the Tx UE 305-1 that indicate one or moreresources (e.g., bandwidths, frequencies, slots or other time periods,and/or spatial filters such as beams) to use when transmitting data tothe Rx UE 305-2 on the sidelink channel. In some aspects, the basestation 110 and the Tx UE 305-1 may be included in a wireless network,such as wireless network 100.

As shown in connection with reference number 505, the Tx UE 305-1 mayperform at least one LBT procedure. For example, as shown in FIG. 5 ,the Tx UE 305-1 may perform at least one LBT procedure when attemptingto transmit data using at least one first bandwidth on at least onesidelink channel to the Rx UE 305-2. As described above, the at leastone LBT procedure may include a CSMA procedure, a CCA procedure, a CSATprocedure, and/or another LBT procedure.

As shown in connection with reference number 510, the Tx UE 305-1 maydetect, while transmitting the data, one or more failures of an LBTprocedure within an amount of time. For example, the Tx UE 305-1 may usea counter that detects a threshold quantity of failures (e.g., thethreshold may include an lbt-FailurelnstanceMaxCount threshold asdefined in 3GPP specifications and/or another standard) before expiry ofa timer (e.g., the timer may include an lbt-FailureDetectionTimer timeras defined in 3GPP specifications and/or another standard). Accordingly,whenever the Tx UE 305-1 detects a failure of an LBT procedure, the TxUE 305-1 may increment the counter, such that the Tx UE 305-1 triggersone or more steps as described in connection with reference numbers 515a, 515 b, 520 a, 520 b, and/or 525 when the counter satisfies thethreshold. The Tx UE 305-1 may reset the counter when the timer expires(e.g., no further failures of an LBT procedure are detected within theamount of time).

In some aspects, the base station 110 may transmit, and the Tx UE 305-1may receive, at least one configuration message, and the amount of timeand/or the threshold may be based at least in part on the at least oneconfiguration message. For example, the base station 110 may indicatethe amount of time and/or the threshold for the Tx UE 305-1 to use.Additionally, or alternatively, the amount of time and/or the thresholdmay be based at least in part on one or more values stored in a memoryof the Tx UE 305-1. For example, the Tx UE 305-1 may be programmed(and/or otherwise preconfigured) to use one or more values defined in3GPP specifications and/or another standard. In another example, the TxUE 305-1 may select one or more values of a plurality of values definedin 3GPP specifications and/or another standard. The Tx UE 305-1 mayselect the one or more values using a look-up table and/or anotherformula that accepts, as input, one or more indicators of quality forthe at least one sidelink channel, one or more indicators of targetthroughput for the at least one sidelink channel, one or moretransmission variables (e.g., transmit power, transmit distance), and/oranother variable, and outputs the amount of time and/or the threshold touse. In another example, the base station 110 may indicate (e.g., in theat least one configuration message) one or more values of a plurality ofvalues defined in 3GPP specifications and/or another standard for the TxUE 305-1 to use.

Additionally, or alternatively, the Rx UE 305-2 may transmit, and the TxUE 305-1 may receive, at least one configuration message, and the amountof time and/or the threshold may be based at least in part on the atleast one configuration message. For example, the Rx UE 305-2 mayindicate the amount of time and/or the threshold for the Tx UE 305-1 touse. In another example, the Rx UE 305-2 may indicate (e.g., in the atleast one configuration message) one or more values of a plurality ofvalues defined in 3GPP specifications and/or another standard for the TxUE 305-1 to use. In another example, the Tx UE 305-1 may determine toignore the at least one configuration message and select one or morevalues to use for the amount of time and/or the threshold (e.g., using aformula or another technique as described above).

In some aspects, one LBT procedure (e.g., performed as described abovein connection with reference number 505) may fail such that the Tx UE305-1 attempts to perform one or more retransmissions. Accordingly, theat least one LBT procedure may include a plurality of LBT proceduresassociated with a transmission and at least one retransmission.

In some aspects, the one or more failures may be associated with atleast one unicast link to at least the Rx UE 305-2, a groupcast link toat least the Rx UE 305-2, and/or another link to at least the Rx UE305-2. The Tx UE 305-1 may aggregate LBT failures across unicast linksto one or more UEs and/or across groupcast links to a plurality of UEs.As an alternative, the Tx UE 305-1 may detect LBT failures separately ondifferent unicast links and/or separately on different groupcast links.Although the description below will focus on sidelink communicationswith the Rx UE 305-2, the Tx UE 305-1 may aggregate LBT failures thatoccur during transmissions to the Rx UE 305-2 with those that occurduring transmissions to other UEs. As an alternative, the Tx UE 305-1may separately detect LBT failures that occur during transmissions todifferent UEs.

Additionally, or alternatively, the one or more failures may beaggregated across one or more PSBCHs, one or more PSCCHs, one or morePSSCHs, one or more PSFCHs, and/or one or more other sidelink channels.For example, such channels may share a link to one or more of the sameUEs, an RB set, a bandwidth part (BWP), and/or one or more otherresources such that the Tx UE 305-1 aggregates LBT failures for thosechannels. In some aspects, when the Tx UE 305-1 operates in mode 2, theTx UE 305-1 may aggregate LBT failures associated with transmissions ofSCI1 with LBT failures associated with transmission of SCI2. As analternative, the Tx UE 305-1 may detect LBT failures associated withtransmissions of SCI1 separately from detecting LBT failures associatedwith transmission of SCI2.

Additionally, or alternatively, the one or more failures may beaggregated across an RB set, a BWP, and/or a plurality of sidelinkchannels. For example, the Tx UE 305-1 may aggregate LBT failures thatoccur on one RB set with those that occur on one or more other RB sets.Additionally, or alternatively, the Tx UE 305-1 may aggregate LBTfailures that occur on one BWP with those that occur on one or moreother BWPs. Additionally, or alternatively, the Tx UE 305-1 mayaggregate LBT failures that occur on one sidelink channel with thosethat occur on one or more other sidelink channels. In some aspects, TxUE 305-1 may further aggregate LBT failures across unicast links and/orgroupcast links, as described above.

Additionally, or alternatively, the one or more failures may beaggregated across a PC5 interface for the at least one sidelink channeland a Uu interface with the base station 110. For example, the Uuinterface may share one or more carriers and/or RB sets with the PC5interface such that the Tx UE 305-1 aggregates LBT failures for thoseone or more carriers and/or RB sets across the PC5 interface and the Uuinterface.

Additionally, or alternatively, the one or more failures may beassociated with one carrier of a plurality of aggregated carriers. Forexample, the Tx UE 305-1 may use one or more carriers associated with aprimary cell (PCell) aggregated with one or more carriers associatedwith one or more secondary cells (SCells). Accordingly, the Tx UE 305-1may aggregate LBT failures across the carriers or may detect LBTfailures separately. For example, the Tx UE 305-1 may detect LBTfailures separately for each carrier or separately for each set ofcarriers associated with a different SCell.

In some aspects, the amount of time and/or the threshold may be based atleast in part on whether the one or more failures are associated with atleast one unicast link, a groupcast link, and/or a broadcasttransmission; whether the one or more failures are associated with aPSBCH, a PSCCH, a PSSCH, a PSFCH, and/or another sidelink channel; whichRB set and/or BWP is associated with the one or more failures; whetherthe one or more failures are associated with a PC5 interface and/or a Uuinterface; and/or which carrier and/or SCell is associated with the oneor more failures. For example, the base station 110 may transmit and/orthe Tx UE 305-1 may select different values for the amount of timeand/or the threshold based at least in part on one or more of thefactors described above.

In some aspects, the Tx UE 305-1 may further cancel pendingtransmissions based at least in part on detecting the one or morefailures and/or cease transmitting one or more broadcast signals (e.g.,a PSBCH transmission, a sidelink synchronization signal block (S-SSB),and/or another broadcast signal) based at least in part on detecting theone or more failures.

As shown in connection with reference number 515 a, the Tx UE 305-1 maytransmit, and the base station 110 may receive, a report indicating theone or more failures. For example, the Tx UE 305-1 may transmit, and thebase station 110 may receive, a medium access control (MAC) layercontrol element (MAC-CE) including the report. In some aspects, the atleast one sidelink channel may include a base station controlledsidelink channel such that the Tx UE 305-1 transmits the report to thebase station 110.

In some aspects, the one or more failures may be associated with one ormore carriers that are associated with one or more SCells. Accordingly,the Tx UE 305-1 may transmit a SidelinkUEInformationNR message, asdefined in 3GPP specifications and/or another standard, that includes acause value set to “LBT failure” and one or more identifiers (e.g., cellIDs) associated with the one or more SCells. As an alternative, the oneor more failures may be associated with one or more carriers that areassociated with a PCell. Accordingly, the Tx UE 305-1 may declare radiolink failure (RLF) on the at least one sidelink channel and transmit aSidelinkUEInformationNR message, as defined in 3GPP specificationsand/or another standard, that includes a cause value set to “LBTfailure.”

In some aspects, the Tx UE 305-1 may select a Uu cell including the basestation 110 to receive the report based at least in part on acorrespondence between a PC5 interface associated with the at least onesidelink channel and a Uu interface associated with the Uu cell. Forexample, the Uu interface may share one or more carriers and/or RB setswith the PC5 interface such that there is a correspondence between thePC5 interface and the Uu interface.

In some aspects, the report may further indicate whether the one or morefailures are associated with at least one unicast link, a groupcastlink, and/or a broadcast transmission; whether the one or more failuresare associated with a PSBCH, a PSCCH, a PSSCH, a PSFCH, and/or anothersidelink channel; which RB set and/or BWP is associated with the one ormore failures; and/or whether the one or more failures are associatedwith a PC5 interface and/or a Uu interface.

Additionally, or alternatively, and as shown in connection withreference number 515 b, the Tx UE 305-1 may transmit, and the Rx UE305-2 may receive, a report indicating the one or more failures. Forexample, the Tx UE 305-1 may transmit, and the Rx UE 305-2 may receive,the report on a different sidelink channel.

In some aspects, the Tx UE 305-1 may be unable to transmit the reportdirectly to the Rx UE 305-2 (e.g., because no other sidelink channelsare established or other sidelink channels also encounter LBT failures).Accordingly, in some aspects, the Tx UE 305-1 may transmit the report toa relay UE on a sidelink channel between the Tx UE 305-1 and the relayUE, and the relay UE may forward the report to the Rx UE 305-2 on asidelink channel between the relay UE and the Rx UE 305-2.

In some aspects, and as shown in connection with reference number 520 a,the base station 110 may transmit, and the Tx UE 305-1 may receive, anindication of at least one second bandwidth to use on the at least onesidelink channel. For example, the base station 110 may determine the atleast one second bandwidth based at least in part on receiving thereport (e.g., as described above in connection with reference number 515a) and may transmit an updated configuration for the at least onesidelink channel that indicates the at least one second bandwidth.

As an alternative, and as shown in connection with reference number 520b, the Tx UE 305-1 may determine at least one second bandwidth to use onthe at least one sidelink channel. For example, the Tx UE 305-1 maydetermine the at least one second bandwidth based at least in part ondetecting the one or more failures and may transmit new SCI (e.g., SCI1)to reserve the at least one second bandwidth for transmitting to the RxUE 305-2.

As shown in connection with reference number 525, the Tx UE 305-1 mayagain perform at least one LBT procedure. For example, as shown in FIG.5 , the Tx UE 305-1 may perform at least one LBT procedure whenattempting to retransmit the data using the at least one secondbandwidth on the at least one sidelink channel to the Rx UE 305-2.Accordingly, when the LBT procedure succeeds, the Tx UE 305-1 mayretransmit the data, to the Rx UE 305-2, using the at least one secondbandwidth on the at least one sidelink channel.

By using techniques described in connection with FIG. 5 , the Tx UE305-1 may report one or more LBT failures on a sidelink channel to thebase station 110 and/or the Rx UE 305-2. As a result, in mode 1, the TxUE 305-1 may obtain one or more new resources from the base station 110to use on the sidelink channel in order to increase quality and/orreliability of sidelink communications with the Rx UE 305-2 as well asconserve processing resources. In mode 2, the Tx UE 305-1 may report theone or more LBT failures to the Rx UE 305-2 such that the Rx UE 305-2may conserve processing resources. Additionally, in some aspects, the TxUE 305-1 may configure a new sidelink channel with the Rx UE 305-2,based at least in part on the one or more LBT failures, in order toincrease quality and/or reliability of sidelink communications with theRx UE 305-2.

As indicated above, FIG. 5 is provided as an example. Other examples maydiffer from what is described with respect to FIG. 5 .

FIG. 6 is a diagram illustrating an example process 600 performed, forexample, by a UE, in accordance with various aspects of the presentdisclosure. Example process 600 is an example where the UE (e.g.,apparatus 800 of FIG. 8 , Tx UE 305-1, and/or UE 120) performsoperations associated with LBT failure reporting for sidelink channels.

As shown in FIG. 6 , in some aspects, process 600 may include detecting,while transmitting data using at least one first bandwidth on at leastone sidelink channel to at least one other UE, one or more failures ofan LBT procedure within an amount of time (block 610). For example, theUE (e.g., using detection component 808, depicted in FIG. 8 ) may detectthe one or more failures of the LBT procedure within the amount of time,as described above.

As further shown in FIG. 6 , in some aspects, process 600 may includetransmitting, to at least one of a base station (e.g., apparatus 900 ofFIG. 9 and/or base station 110) or the at least one other UE, a reportindicating the one or more failures (block 620). For example, the UE(e.g., using transmission component 804, depicted in FIG. 8 ) maytransmit the report indicating the one or more failures, as describedabove.

Process 600 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the at least one sidelink channel includes a basestation controlled sidelink channel, and the report is transmitted tothe base station.

In a second aspect, alone or in combination with the first aspect,process 600 further includes retransmitting the data (e.g., usingtransmission component 804), to the at least one other UE, using atleast one second bandwidth on the at least one sidelink channel.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the at least one sidelink channel comprises a PSBCH,a PSCCH, a PSSCH, a PSFCH, or a combination thereof.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, the one or more failures are associatedwith at least one unicast link to the at least one other UE, a groupcastlink to the at least one other UE, or a combination thereof.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, the amount of time is based at least in part onwhether the one or more failures are associated with at least oneunicast link or with a groupcast link.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, the one or more failures are aggregated across anRB set, a BWP, or a plurality of sidelink channels.

In a seventh aspect, alone or in combination with one or more of thefirst through sixth aspects, the one or more failures are aggregatedacross a PC5 interface for the at least one sidelink channel and a Uuinterface with the base station.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, process 600 further includes receiving atleast one configuration message (e.g., using reception component 802,depicted in FIG. 8 ) from the base station, and the amount of time isbased at least in part on the at least one configuration message.

In a ninth aspect, alone or in combination with one or more of the firstthrough eighth aspects, the amount of time is based at least in part ona value stored in the memory.

In a tenth aspect, alone or in combination with one or more of the firstthrough ninth aspects, the one or more failures are associated with onecarrier of a plurality of aggregated carriers.

In an eleventh aspect, alone or in combination with one or more of thefirst through tenth aspects, process 600 further includes cancelingpending transmissions (e.g., using scheduling component 810, depicted inFIG. 8 ) based at least in part on detecting the one or more failures,and ceasing transmitting one or more broadcast signals (e.g., usingtransmission component 804) based at least in part on detecting the oneor more failures.

In a twelfth aspect, alone or in combination with one or more of thefirst through eleventh aspects, the report is transmitted to the atleast one other UE.

Although FIG. 6 shows example blocks of process 600, in some aspects,process 600 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 6 .Additionally, or alternatively, two or more of the blocks of process 600may be performed in parallel.

FIG. 7 is a diagram illustrating an example process 700 performed, forexample, by a base station, in accordance with various aspects of thepresent disclosure. Example process 700 is an example where the basestation (e.g., apparatus 900 of FIG. 9 and/or base station 110) performsoperations associated with LBT failure reporting for sidelink channels.

As shown in FIG. 7 , in some aspects, process 700 may include receiving,from a UE (e.g., apparatus 800 of FIG. 8 , Tx UE 305-1, and/or UE 120),a report indicating one or more failures of an LBT procedure associatedwith at least one first bandwidth on at least one sidelink channel(block 710). For example, the base station (e.g., using receptioncomponent 902, depicted in FIG. 9 ) may receive the report indicatingthe one or more failures of the LBT procedure, as described above.

As further shown in FIG. 7 , in some aspects, process 700 may includetransmitting, to the UE, an indication of at least one second bandwidthto use on the at least one sidelink channel (block 720). For example,the base station (e.g., using transmission component 904, depicted inFIG. 9 ) may transmit the indication of the at least one secondbandwidth to use, as described above.

Process 700 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the at least one sidelink channel comprises a PSBCH,a PSCCH, a PSSCH, a PSFCH, or a combination thereof.

In a second aspect, alone or in combination with the first aspect, theone or more failures are associated with at least one unicast linkbetween the UE and at least one other UE, a groupcast link between theUE and at least one other UE, or a combination thereof.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the one or more failures are associated with anamount of time that is based at least in part on whether the one or morefailures are associated with at least one unicast link or with agroupcast link.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, the one or more failures are aggregatedacross an RB set, a BWP, or a plurality of sidelink channels.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, the one or more failures are aggregated across aPC5 interface for the at least one sidelink channel and a Uu interfacewith the base station.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, process 700 further includes transmitting atleast one configuration message (e.g., using transmission component 904)to the UE, and the one or more failures are associated with an amount oftime that is based at least in part on the at least one configurationmessage.

In a seventh aspect, alone or in combination with one or more of thefirst through sixth aspects, the one or more failures are associatedwith an amount of time that is based at least in part on a value storedin the memory.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, the one or more failures are associatedwith one carrier of a plurality of aggregated carriers.

Although FIG. 7 shows example blocks of process 700, in some aspects,process 700 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 7 .Additionally, or alternatively, two or more of the blocks of process 700may be performed in parallel.

FIG. 8 is a block diagram of an example apparatus 800 for wirelesscommunication. The apparatus 800 may be a UE, or a UE may include theapparatus 800. In some aspects, the apparatus 800 includes a receptioncomponent 802 and a transmission component 804, which may be incommunication with one another (for example, via one or more busesand/or one or more other components). As shown, the apparatus 800 maycommunicate with another apparatus 806 (such as a UE, a base station, oranother wireless communication device) using the reception component 802and the transmission component 804. As further shown, the apparatus 800may include one or more of a detection component 808 or a schedulingcomponent 810, among other examples.

In some aspects, the apparatus 800 may be configured to perform one ormore operations described herein in connection with FIG. 5 .Additionally, or alternatively, the apparatus 800 may be configured toperform one or more processes described herein, such as process 600 ofFIG. 6 , or a combination thereof. In some aspects, the apparatus 800and/or one or more components shown in FIG. 8 may include one or morecomponents of the UE described above in connection with FIG. 2 .Additionally, or alternatively, one or more components shown in FIG. 8may be implemented within one or more components described above inconnection with FIG. 2 . Additionally, or alternatively, one or morecomponents of the set of components may be implemented at least in partas software stored in a memory. For example, a component (or a portionof a component) may be implemented as instructions or code stored in anon-transitory computer-readable medium and executable by a controlleror a processor to perform the functions or operations of the component.

The reception component 802 may receive communications, such asreference signals, control information, data communications, or acombination thereof, from the apparatus 806. The reception component 802may provide received communications to one or more other components ofthe apparatus 800. In some aspects, the reception component 802 mayperform signal processing on the received communications (such asfiltering, amplification, demodulation, analog-to-digital conversion,demultiplexing, deinterleaving, de-mapping, equalization, interferencecancellation, or decoding, among other examples), and may provide theprocessed signals to the one or more other components of the apparatus806. In some aspects, the reception component 802 may include one ormore antennas, a demodulator, a MIMO detector, a receive processor, acontroller/processor, a memory, or a combination thereof, of the UEdescribed above in connection with FIG. 2 .

The transmission component 804 may transmit communications, such asreference signals, control information, data communications, or acombination thereof, to the apparatus 806. In some aspects, one or moreother components of the apparatus 806 may generate communications andmay provide the generated communications to the transmission component804 for transmission to the apparatus 806. In some aspects, thetransmission component 804 may perform signal processing on thegenerated communications (such as filtering, amplification, modulation,digital-to-analog conversion, multiplexing, interleaving, mapping, orencoding, among other examples), and may transmit the processed signalsto the apparatus 806. In some aspects, the transmission component 804may include one or more antennas, a modulator, a transmit MIMOprocessor, a transmit processor, a controller/processor, a memory, or acombination thereof, of the UE described above in connection with FIG. 2. In some aspects, the transmission component 804 may be co-located withthe reception component 802 in a transceiver.

In some aspects, the detection component 808 may detect, while thetransmission component 804 transmits data using at least one firstbandwidth on at least one sidelink channel to at least one other UE, oneor more failures of an LBT procedure within an amount of time. In someaspects, the detection component 808 may include one or more antennas, ademodulator, a MIMO detector, a receive processor, acontroller/processor, a memory, or a combination thereof, of the UEdescribed above in connection with FIG. 2 . Accordingly, thetransmission component 804 may transmit, to at least one of theapparatus 806 or the at least one other UE, a report indicating the oneor more failures. In some aspects, the transmission component 804 mayfurther retransmit the data, to the at least one other UE, using atleast one second bandwidth on the at least one sidelink channel.

In some aspects, the reception component 802 may receive at least oneconfiguration message from the apparatus 806, such that the amount oftime is based at least in part on the at least one configurationmessage.

In some aspects, the scheduling component 810 may cancel pendingtransmissions based at least in part on the detection component 808detecting the one or more failures. In some aspects, the schedulingcomponent 810 may include one or more antennas, a modulator, a transmitMIMO processor, a transmit processor, a controller/processor, a memory,or a combination thereof, of the UE described above in connection withFIG. 2 . Additionally, or alternatively the transmission component 804may cease transmitting one or more broadcast signals based at least inpart on the detection component 808 detecting the one or more failures.

The number and arrangement of components shown in FIG. 8 are provided asan example. In practice, there may be additional components, fewercomponents, different components, or differently arranged componentsthan those shown in FIG. 8 . Furthermore, two or more components shownin FIG. 8 may be implemented within a single component, or a singlecomponent shown in FIG. 8 may be implemented as multiple, distributedcomponents. Additionally, or alternatively, a set of (one or more)components shown in FIG. 8 may perform one or more functions describedas being performed by another set of components shown in FIG. 8 .

FIG. 9 is a block diagram of an example apparatus 900 for wirelesscommunication. The apparatus 900 may be a base station, or a basestation may include the apparatus 900. In some aspects, the apparatus900 includes a reception component 902 and a transmission component 904,which may be in communication with one another (for example, via one ormore buses and/or one or more other components). As shown, the apparatus900 may communicate with another apparatus 906 (such as a UE, a basestation, or another wireless communication device) using the receptioncomponent 902 and the transmission component 904. As further shown, theapparatus 900 may include a determination component 908, among otherexamples.

In some aspects, the apparatus 900 may be configured to perform one ormore operations described herein in connection with FIG. 5 .Additionally, or alternatively, the apparatus 900 may be configured toperform one or more processes described herein, such as process 700 ofFIG. 7 , or a combination thereof. In some aspects, the apparatus 900and/or one or more components shown in FIG. 9 may include one or morecomponents of the base station described above in connection with FIG. 2. Additionally, or alternatively, one or more components shown in FIG. 9may be implemented within one or more components described above inconnection with FIG. 2 . Additionally, or alternatively, one or morecomponents of the set of components may be implemented at least in partas software stored in a memory. For example, a component (or a portionof a component) may be implemented as instructions or code stored in anon-transitory computer-readable medium and executable by a controlleror a processor to perform the functions or operations of the component.

The reception component 902 may receive communications, such asreference signals, control information, data communications, or acombination thereof, from the apparatus 906. The reception component 902may provide received communications to one or more other components ofthe apparatus 900. In some aspects, the reception component 902 mayperform signal processing on the received communications (such asfiltering, amplification, demodulation, analog-to-digital conversion,demultiplexing, deinterleaving, de-mapping, equalization, interferencecancellation, or decoding, among other examples), and may provide theprocessed signals to the one or more other components of the apparatus906. In some aspects, the reception component 902 may include one ormore antennas, a demodulator, a MIMO detector, a receive processor, acontroller/processor, a memory, or a combination thereof, of the basestation described above in connection with FIG. 2 .

The transmission component 904 may transmit communications, such asreference signals, control information, data communications, or acombination thereof, to the apparatus 906. In some aspects, one or moreother components of the apparatus 906 may generate communications andmay provide the generated communications to the transmission component904 for transmission to the apparatus 906. In some aspects, thetransmission component 904 may perform signal processing on thegenerated communications (such as filtering, amplification, modulation,digital-to-analog conversion, multiplexing, interleaving, mapping, orencoding, among other examples), and may transmit the processed signalsto the apparatus 906. In some aspects, the transmission component 904may include one or more antennas, a modulator, a transmit MIMOprocessor, a transmit processor, a controller/processor, a memory, or acombination thereof, of the base station described above in connectionwith FIG. 2 . In some aspects, the transmission component 904 may beco-located with the reception component 902 in a transceiver.

In some aspects, the reception component 902 may receive, from theapparatus 906, a report indicating one or more failures of an LBTprocedure associated with at least one first bandwidth on at least onesidelink channel. Accordingly, the transmission component 904 maytransmit, to the apparatus 906, an indication of at least one secondbandwidth to use on the at least one sidelink channel. For example, thedetermination component 908 may determine the at least one secondbandwidth based at least in part on the report. In some aspects, thedetermination component 908 may include a receive processor, a transmitprocessor, a controller/processor, a memory, or a combination thereof,of the base station described above in connection with FIG. 2 .

In some aspects, the transmission component 904 may transmit at leastone configuration message to the apparatus 906, and one or more failuresmay be associated with an amount of time that is based at least in parton the at least one configuration message.

The number and arrangement of components shown in FIG. 9 are provided asan example. In practice, there may be additional components, fewercomponents, different components, or differently arranged componentsthan those shown in FIG. 9 . Furthermore, two or more components shownin FIG. 9 may be implemented within a single component, or a singlecomponent shown in FIG. 9 may be implemented as multiple, distributedcomponents. Additionally, or alternatively, a set of (one or more)components shown in FIG. 9 may perform one or more functions describedas being performed by another set of components shown in FIG. 9 .

The following provides an overview of some aspects of the presentdisclosure:

Aspect 1: A method of wireless communication performed by a userequipment (UE), comprising: detecting, while transmitting data using atleast one first bandwidth on at least one sidelink channel to at leastone other UE, one or more failures of a listen-before-talk (LBT)procedure within an amount of time; and transmitting, to at least one ofa base station or the at least one other UE, a report indicating the oneor more failures.

Aspect 2: The method of aspect 1, wherein the at least one sidelinkchannel includes a base station controlled sidelink channel, and thereport is transmitted to the base station.

Aspect 3: The method of any of aspects 1 through 2, further comprising:retransmitting the data, to the at least one other UE, using at leastone second bandwidth on the at least one sidelink channel.

Aspect 4: The method of any of aspects 1 through 3, wherein the at leastone sidelink channel comprises a physical sidelink broadcast channel(PSBCH), a physical sidelink control channel (PSCCH), a physicalsidelink shared channel (PSSCH), a physical sidelink feedback channel(PSFCH), or a combination thereof.

Aspect 5: The method of any of aspects 1 through 4, wherein the one ormore failures are associated with at least one unicast link to the atleast one other UE, a groupcast link to the at least one other UE, or acombination thereof.

Aspect 6: The method of any of aspects 1 through 5, wherein the amountof time is based at least in part on whether the one or more failuresare associated with at least one unicast link or with a groupcast link.

Aspect 7: The method of any of aspects 1 through 6, wherein the one ormore failures are aggregated across a resource block (RB) set, abandwidth part (BWP), or a plurality of sidelink channels.

Aspect 8: The method of any of aspects 1 through 7, wherein the one ormore failures are aggregated across a PC5 interface for the at least onesidelink channel and a Uu interface with the base station.

Aspect 9: The method of any of aspects 1 through 8, further comprising:receiving at least one configuration message from the base station,wherein the amount of time is based at least in part on the at least oneconfiguration message.

Aspect 10: The method of any of aspects 1 through 9, wherein the amountof time is based at least in part on a value stored in the memory.

Aspect 11: The method of any of aspects 1 through 10, wherein the one ormore failures are associated with one carrier of a plurality ofaggregated carriers.

Aspect 12: The method of any of aspects 1 through 11, furthercomprising: canceling pending transmissions based at least in part ondetecting the one or more failures; and ceasing transmitting one or morebroadcast signals based at least in part on detecting the one or morefailures.

Aspect 13: The method of any of aspects 1 through 12, wherein the reportis transmitted to the at least one other UE.

Aspect 14: A method of wireless communication performed by a basestation, comprising: receiving, from a UE, a report indicating one ormore failures of an LBT procedure associated with at least one firstbandwidth on at least one sidelink channel; and transmitting, to the UE,an indication of at least one second bandwidth to use on the at leastone sidelink channel.

Aspect 15: The method of aspect 14, wherein the at least one sidelinkchannel comprises a PSBCH, a PSCCH, a PSSCH, a PSFCH, or a combinationthereof.

Aspect 16: The method of any of aspects 14 through 15, wherein the oneor more failures are associated with at least one unicast link betweenthe UE and at least one other UE, a groupcast link between the UE and atleast one other UE, or a combination thereof.

Aspect 17: The method of any of aspects 14 through 16, wherein the oneor more failures are associated with an amount of time that is based atleast in part on whether the one or more failures are associated with atleast one unicast link or with a groupcast link.

Aspect 18: The method of any of aspects 14 through 17, wherein the oneor more failures are aggregated across an RB set, a BWP, or a pluralityof sidelink channels.

Aspect 19: The method of any of aspects 14 through 18, wherein the oneor more failures are aggregated across a PC5 interface for the at leastone sidelink channel and a Uu interface with the base station.

Aspect 20: The method of any of aspects 14 through 19, furthercomprising: transmitting at least one configuration message to the UE,wherein the one or more failures are associated with an amount of timethat is based at least in part on the at least one configurationmessage.

Aspect 21: The method of any of aspects 14 through 20, wherein the oneor more failures are associated with an amount of time that is based atleast in part on a value stored in the memory.

Aspect 22: The method of any of aspects 14 through 21, wherein the oneor more failures are associated with one carrier of a plurality ofaggregated carriers.

Aspect 23: An apparatus for wireless communication at a device,comprising a processor; memory coupled with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to perform the method of one or more aspects ofaspects 1-13.

Aspect 24: A device for wireless communication, comprising a memory andone or more processors coupled to the memory, the memory and the one ormore processors configured to perform the method of one or more aspectsof aspects 1-13.

Aspect 25: An apparatus for wireless communication, comprising at leastone means for performing the method of one or more aspects of aspects1-13.

Aspect 26: A non-transitory computer-readable medium storing code forwireless communication, the code comprising instructions executable by aprocessor to perform the method of one or more aspects of aspects 1-13.

Aspect 27: A non-transitory computer-readable medium storing a set ofinstructions for wireless communication, the set of instructionscomprising one or more instructions that, when executed by one or moreprocessors of a device, cause the device to perform the method of one ormore aspects of aspects 1-13.

Aspect 28: An apparatus for wireless communication at a device,comprising a processor; memory coupled with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to perform the method of one or more aspects ofaspects 14-22.

Aspect 29: A device for wireless communication, comprising a memory andone or more processors coupled to the memory, the memory and the one ormore processors configured to perform the method of one or more aspectsof aspects 14-22.

Aspect 30: An apparatus for wireless communication, comprising at leastone means for performing the method of one or more aspects of aspects14-22.

Aspect 31: A non-transitory computer-readable medium storing code forwireless communication, the code comprising instructions executable by aprocessor to perform the method of one or more aspects of aspects 14-22.

Aspect 32: A non-transitory computer-readable medium storing a set ofinstructions for wireless communication, the set of instructionscomprising one or more instructions that, when executed by one or moreprocessors of a device, cause the device to perform the method of one ormore aspects of aspects 14-22.

The foregoing disclosure provides illustration and description, but isnot intended to be exhaustive or to limit the aspects to the preciseforms disclosed. Modifications and variations may be made in light ofthe above disclosure or may be acquired from practice of the aspects.

As used herein, the term “component” is intended to be broadly construedas hardware and/or a combination of hardware and software. “Software”shall be construed broadly to mean instructions, instruction sets, code,code segments, program code, programs, subprograms, software modules,applications, software applications, software packages, routines,subroutines, objects, executables, threads of execution, procedures,and/or functions, among other examples, whether referred to as software,firmware, middleware, microcode, hardware description language, orotherwise. As used herein, a processor is implemented in hardware and/ora combination of hardware and software. It will be apparent that systemsand/or methods described herein may be implemented in different forms ofhardware and/or a combination of hardware and software. The actualspecialized control hardware or software code used to implement thesesystems and/or methods is not limiting of the aspects. Thus, theoperation and behavior of the systems and/or methods were describedherein without reference to specific software code—it being understoodthat software and hardware can be designed to implement the systemsand/or methods based, at least in part, on the description herein.

As used herein, satisfying a threshold may, depending on the context,refer to a value being greater than the threshold, greater than or equalto the threshold, less than the threshold, less than or equal to thethreshold, equal to the threshold, not equal to the threshold, or thelike.

Even though particular combinations of features are recited in theclaims and/or disclosed in the specification, these combinations are notintended to limit the disclosure of various aspects. In fact, many ofthese features may be combined in ways not specifically recited in theclaims and/or disclosed in the specification. Although each dependentclaim listed below may directly depend on only one claim, the disclosureof various aspects includes each dependent claim in combination withevery other claim in the claim set. As used herein, a phrase referringto “at least one of” a list of items refers to any combination of thoseitems, including single members. As an example, “at least one of: a, b,or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well asany combination with multiples of the same element (e.g., a-a, a-a-a,a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or anyother ordering of a, b, and c).

No element, act, or instruction used herein should be construed ascritical or essential unless explicitly described as such. Also, as usedherein, the articles “a” and “an” are intended to include one or moreitems and may be used interchangeably with “one or more.” Further, asused herein, the article “the” is intended to include one or more itemsreferenced in connection with the article “the” and may be usedinterchangeably with “the one or more.” Furthermore, as used herein, theterms “set” and “group” are intended to include one or more items (e.g.,related items, unrelated items, or a combination of related andunrelated items), and may be used interchangeably with “one or more.”Where only one item is intended, the phrase “only one” or similarlanguage is used. Also, as used herein, the terms “has,” “have,”“having,” or the like are intended to be open-ended terms. Further, thephrase “based on” is intended to mean “based, at least in part, on”unless explicitly stated otherwise. Also, as used herein, the term “or”is intended to be inclusive when used in a series and may be usedinterchangeably with “and/or,” unless explicitly stated otherwise (e.g.,if used in combination with “either” or “only one of”).

What is claimed is:
 1. A user equipment (UE) for wireless communication,comprising: a memory; and one or more processors operatively coupled tothe memory, the memory and the one or more processors configured to:detect, while transmitting data using at least one first bandwidth on atleast one sidelink channel to at least one other UE, one or morefailures of a listen-before-talk (LBT) procedure within an amount oftime, wherein the amount of time is based at least in part on whetherthe one or more failures are associated with at least one unicast linkor with a groupcast link; and transmit, to at least one of a networknode or the at least one other UE, a report indicating the one or morefailures.
 2. The UE of claim 1, wherein the at least one sidelinkchannel includes a network node controlled sidelink channel, and thereport is transmitted to the network node.
 3. The UE of claim 1, whereinthe memory and the one or more processors are further configured to:retransmit the data, to the at least one other UE, using at least onesecond bandwidth on the at least one sidelink channel.
 4. The UE ofclaim 1, wherein the at least one sidelink channel comprises a physicalsidelink broadcast channel (PSBCH), a physical sidelink control channel(PSCCH), a physical sidelink shared channel (PSSCH), a physical sidelinkfeedback channel (PSFCH), or a combination thereof.
 5. The UE of claim1, wherein the one or more failures are associated with at least oneunicast link to the at least one other UE, a groupcast link to the atleast one other UE, or a combination thereof.
 6. The UE of claim 1,wherein the one or more failures are aggregated across a resource block(RB) set, a bandwidth part (BWP), or a plurality of sidelink channels.7. The UE of claim 1, wherein the one or more failures are aggregatedacross a PC5 interface for the at least one sidelink channel and a Uuinterface with the network node.
 8. The UE of claim 1, wherein thememory and the one or more processors are further configured to: receiveat least one configuration message from the network node, wherein theamount of time is based at least in part on the at least oneconfiguration message.
 9. The UE of claim 1, wherein the amount of timeis based at least in part on a value stored in the memory.
 10. The UE ofclaim 1, wherein the one or more failures are associated with onecarrier of a plurality of aggregated carriers.
 11. The UE of claim 1,wherein the memory and the one or more processors are further configuredto: cancel pending transmissions based at least in part on detecting theone or more failures; and cease transmitting one or more broadcastsignals based at least in part on detecting the one or more failures.12. The UE of claim 1, wherein the report is transmitted to the at leastone other UE.
 13. A network node for wireless communication, comprising:a memory; and one or more processors operatively coupled to the memory,the memory and the one or more processors configured to: receive, from auser equipment (UE), a report indicating one or more failures of alisten-before-talk (LBT) procedure associated with at least one firstbandwidth on at least one sidelink channel within an amount of time,wherein the amount of time is based at least in part on whether the oneor more failures are associated with at least one unicast link or with agroupcast link; and transmit, to the UE, an indication of at least onesecond bandwidth to use on the at least one sidelink channel.
 14. Thenetwork node of claim 13, wherein the at least one sidelink channelcomprises a physical sidelink broadcast channel (PSBCH), a physicalsidelink control channel (PSCCH), a physical sidelink shared channel(PSSCH), a physical sidelink feedback channel (PSFCH), or a combinationthereof.
 15. The network node of claim 13, wherein the one or morefailures are associated with at least one unicast link between the UEand at least one other UE, a groupcast link between the UE and at leastone other UE, or a combination thereof.
 16. The network node of claim13, wherein the one or more failures are associated with an amount oftime that is based at least in part on whether the one or more failuresare associated with at least one unicast link or with a groupcast link.17. The network node of claim 13, wherein the one or more failures areaggregated across a resource block (RB) set, a bandwidth part (BWP), ora plurality of sidelink channels.
 18. The network node of claim 13,wherein the one or more failures are aggregated across a PC5 interfacefor the at least one sidelink channel and a Uu interface with thenetwork node.
 19. The network node of claim 13, wherein the memory andthe one or more processors are further configured to: transmit at leastone configuration message to the UE, wherein the one or more failuresare associated with an amount of time that is based at least in part onthe at least one configuration message.
 20. The network node of claim13, wherein the one or more failures are associated with an amount oftime that is based at least in part on a value stored in the memory. 21.The network node of claim 13, wherein the one or more failures areassociated with one carrier of a plurality of aggregated carriers.
 22. Amethod of wireless communication performed by a user equipment (UE),comprising: detecting, while transmitting data using at least one firstbandwidth on at least one sidelink channel to at least one other UE, oneor more failures of a listen-before-talk (LBT) procedure within anamount of time, wherein the amount of time is based at least in part onwhether the one or more failures are associated with at least oneunicast link or with a groupcast link; and transmitting, to at least oneof a network node or the at least one other UE, a report indicating theone or more failures.
 23. The method of claim 22, wherein the at leastone sidelink channel includes a network node controlled sidelinkchannel, and the report is transmitted to the network node.
 24. Themethod of claim 22, further comprising: retransmitting the data, to theat least one other UE, using at least one second bandwidth on the atleast one sidelink channel.
 25. The method of claim 22, wherein the oneor more failures are aggregated across a resource block (RB) set, abandwidth part (BWP), or a plurality of sidelink channels.
 26. Themethod of claim 22, wherein the one or more failures are aggregatedacross a PC5 interface for the at least one sidelink channel and a Uuinterface with the network node.
 27. The method of claim 22, wherein theone or more failures are associated with one carrier of a plurality ofaggregated carriers.
 28. The method of claim 22, further comprising:canceling pending transmissions based at least in part on detecting theone or more failures; and ceasing transmitting one or more broadcastsignals based at least in part on detecting the one or more failures.29. A method of wireless communication performed by a network node,comprising: receiving, from a user equipment (UE), a report indicatingone or more failures of a listen-before-talk (LBT) procedure associatedwith at least one first bandwidth on at least one sidelink channelwithin an amount of time, wherein the amount of time is based at leastin part on whether the one or more failures are associated with at leastone unicast link or with a groupcast link; and transmitting, to the UE,an indication of at least one second bandwidth to use on the at leastone sidelink channel.